Tube-cleaning projectile



June 28, 192; G c. COOK AL 1,634,094

TUBE CLEANING PROJECTILE Fiied Feb. 20, 1926 INVENI'ORS George C foo/ra Jon A. Coleman ATTORNEY Patented June 28, 1927.

warren stares PATENT OFFICE.

GEORGE C. COOK, OF MILLINGTON, NEW JERSEY, AND JOHN A. COLEMAN, OF WOOD- HAVEN, NEW YORK.

Application filed February The invention relates to a tube cleaning projectile or plug such as may be employed in connection with the cleaning of condenser, boiler and other types of tubes, and comprising an elongated cylindrical body of resilient material. 7 v It has for its object a plug of this character which will be effective in action thru the provision of greatly increased length of cutting edge, and will be durable and comparatively inexpensive in construction. As is understood, the plug is designed to pass thru the interior of a tube and'to'clean the inner surface thereof from accumulations of slime, mud and loose dirt which destroythe efficiency of the condenser. or other apparatus. The invention has for a further ob ect the provision of a plurality of more or less hehcally directed cutting edges, to cut;

diagonally, as well as of a transversely di rected cutting edge, the former edges also being designed to turn over slightly in in serting the plug into atube while the latter is compressed against the inner wall of a tube. More particularly, the invention comprises a member whose general outline 1s cy-' lindrical and which itself is composed of.

rubber or similar resilient material, the entrance portion and greater part of the member beingof slightly larger diameter than the bore of the tube for which it isdesigned and having in its periphery a plurality of grooves or passages extending generally in the longltudinal axis of the plug. The same are in the nature of helical grooves of rectangular cross section and of a pitch such that the one groove overlapsthe beginning of an adjacent groove. Moreover, a transverse peripheral groove, also of rectangular section, is provided between the helically grooved portion and the head of the plug, the latter tapering from its outer end to the said transverse peripheral groove'and being of slightly greater diameter at its outer end than the bore of the tube with which it is to be used, while at its transverse groove end it is of substantially the diameter of said bore or preferably slightly less.

The nature of the invention, however, will best be understood when described in connection with the accompanying drawings, in which- Fig. 1 shows the novel plug in elevation, and Fig. 2' is an end View thereof.

Referring to the drawings, the plug is 20,1926. SerialNo. 89,562.

shown as comprising a unitary member as of a single piece of durable elastic material as tough elastic rubber, the same bein moulded to a generally cylindrical outlinii and of alength about three times its diameter. For example, for a tube bore, 1 have found a plugof a length of 2 satisfactory; and in selecting material of the nature set forth not only is the same comparatively inexpensive and well able to withstandthe severe punishment to which a plug is subjected, but it is admirably adapted to the novel construction of cutting edges set forth hereinafter.

The novel plugcomprises a principal cut- --lygreater diameter near its outer end-than the bore of the tube the plug is designed to clean, while the portion 10 is of somewhat greater diameter than the bore of the tube to be cleaned. The principal cleaning action is effected by the latter portion, which for this purpose is provided over its periphery with a plurality of longitudinally directed helical grooves 12 or multiplicity of square threads 12 which are substantially rectangular 1n sectlon and afford sharp edges 13 for cutting or scraping, the material from the interior surface ofthe tube.

The planes of a cutting edge are at angles of not over 90 to each other and the pitch of the successive helices is such that the end of the one overlaps the beginning of an ad- Jacent groove and thus provides always a cutting edge along the line of motion. There is, furthermore, provided over the, periphery of said portion 10 a transversely directed groove 14 of substantially the same depth as the grooves 12, and the same at fords a further cutting or scraping edge 15.

The head 11 of the plug is tapered as indicated, the diameter at the cutting edge 15 being substantially equal to or preferably slightly less than the bore of the tube to be cleaned, while at the outer edge 16 the diameter is slightly greater than said bore to bending over sufficiently to admit the plug and then exerting an expanding forcible pressure against the inner wall of the tube to be cleaned as-the plug is driven thru under the impetus of the pressure exerted behind the head 11. This causes a plug to travel rapidly thru a tube, and due to the high degree of compression existing between the plug and a tube the edges 13 are held firmly inposition and do not climb over the material to be removed. The edges 13'as well as the edge 15, which latter will be forced tightly against the tube wall due to the compression action of the fluid pressure on head 11, thus effect a scraping or cut-ting action on the foreign matter; and

the plug carries mud, slime and dirt ahead of it which is finally discharged from the opposite end of a tube as the plug is projected therefrom. This cleaning action is enhanced, also, by the initial resistance offered to the passage of the plug thru forcing of the cylindrical grooved portion 10 into and thru a tube. It will be understood, that, due to the resilient nature of these edges, a continuous, though resilient, expanding forcible pressure is exerted thereby against-the inner wall of the tube and that a very effective cleaning action is had thereby. Moreover, the material composing the plug is such as makes the plug Wholly harmless to a tube thru which it is forced.

We claim I 1. A tube cleaning projectile, comprising a substantially cylindrical unitary member, solely of resilient material, having a helically grooved entrance portion and a head or sealing portion, the diameter of the former being not less than the diameter of the latter.

2. A tube cleaning projectile, comprising a substantially cylindrical unitary member, solely of resilient material, having a helically grooved entrance portion and a head or sealing portion separated therefrom by a transverse peripheral groove formed in the member and affording a cleaning edge, the diameter of said entrance portion being not less than the diameter of the head or sealing portion. 7

3. A tube cleaning projectile, comprising a substantially cylindrical unitary member, solely of resilient material, having a helically grooved entrance portion, and ahead portion of smaller diameter at its inner end than the adjacent end of the grooved portion, said head portion tapering to a'slightly larger diameter at the outer end.

4-. A tube cleaning projectile, comprising a substantially cylindrical. unitary member, solely of resilient material, having a helically grooved entrance portion and a head portion separated by a transverse peripheral groove formed in said member and affording a cleaning edge, the head portion at its cleaning edge being of smaller diameter than the grooved portion and tapering to a slightly larger diameter at its outer end.

In testimony whereof we affix our signatures.

GEORGE C. COOK. JOHN A. COLEMAN. 

